Tilda Publishing

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Tilda Publishing

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

2025, No. 4, ABSTRACTS

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Study of thermophysical properties of fine-grained graphite MPG-7 in the range of 1000 – 2000 °С at laser heating

M. V. Torchick, M. A. Kotov, V. N. Androsenko, F. V. Filippov, N. G. Solovyov,
A. N. Shemyakin, M. Yu. Yakimov, A. V. Chaplygin, S. S. Galkin

Ishlinsky Institute for Problems in Mechanics of the Russian Academy of Sciences (IPMech RAS),
101-1, Prospekt Vernadskogo, 119526 Moscow, Russia
E-mail: mari.torchick@ipmnet.ru; kotov@ipmnet.ru; androsenko@ipmnet.ru; filippov@ipmnet.ru; solovyov@lantanlaser.ru;
shemyakin@lantanlaser.ru; yakimov@lantanlaser.ru; chaplygin@ipmnet.ru; galkin@ipmnet.ru

The paper is devoted to the development of a method for determining the heat capacity and thermal conductivity of hightemperature materials by solving the inverse heat conduction problem in a computational model and comparing the results obtained with experimental data. A series of experiments on heating by laser radiation of samples from graphite MPG-7 is performed, as well as a number of calculations in accordance with the initial and boundary conditions of the experiment. The coincidence of calculated and experimental data confirms the possibility of using the proposed calculation-experimental method to determine the thermophysical properties of new materials.

Keywords: heat capacity, thermal conductivity, thermophysical properties, graphite, high temperature.

DOI: 10.30791/0015-3214-2025-4-5-19

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Modelling the heating of epoxy compounds in microwave chambers of different types

A. S. Sivak¹, S. G. Kalganova^1,2, S. V. Trigorly¹, Y. A. Kadykova^1,2,
E. Yu. Vasinkina¹, T. P. Sivak¹, G. V. Sakhadzhi<sup>1,2

1</sup> JSC “Scientific Production Enterprice “Kontakt”, bldg. 1, B.V. Spitsyn str., 410086 Saratov, Russia
E-mail: nayka@kontakt-saratov.ru
² Saratov State University, 83, Astrakhanskaya str., 410012 Saratov, Russia
E-mail: sahadj@yandex.ru

In the technology of obtaining composites the actual problem is the reduction of curing time of polymer binders, reduction of energy consumption for technological processes without reducing the quality of composites. The aim of the work is the development of microwave chamber designs on the basis of mathematical modelling and determination of heating modes of epoxy compounds in binder curing processes for obtaining high-energy radio-absorbing composites. The solution of the interrelated equations of electrodynamics and heat conduction was performed using the finite element method, which was implemented in the COMSOL Multiphysics program. Numerical investigations of temperature and electric fields distribution in epoxy compound were carried out taking into account heating modes, microwave chamber design, and physical properties of the composite. It is established that for microwave heating of the compound containing epoxy resin ED-20 with silicon carbide filler it is reasonable to use working microwave chambers on quasi-coaxial waveguide and with waveguide-slot radiators of periodic action. The optimum modes of microwave curing of epoxy compound have been determined: microwave exposure time, power, speed of rotation and movement of the mold with compound in microwave chambers. To achieve the required temperature of curing of epoxy compound, the algorithm of step-by-step regulation of microwave power depending on the temperature in the control point was used, which allows to achieve a uniform distribution of the temperature field in the volume of the compound and accelerate the technological process of obtaining the composite. The proposed approach to solving the
problems of heating epoxy compounds in microwave chambers of various types and the results of modelling can be used in the development of microwave chambers in the technologies of curing and modification of various compounds, as well as for the construction of algorithms and control systems of microwave installations.

Keywords: mathematical modelling, microwave heating, epoxy compound, electrodynamics, thermal conductivity, microwave chamber, curing, power regulation.

DOI: 10.30791/0015-3214-2025-4-20-32

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Simulation of laser welding of aluminum foam plates using a monolithic insertion

V. G. Shchukin, A. N. Cherepanov, V. N. Popov

Khristianovich Institute of Theoretical and Applied Mechanics SB RAS (ITAM SB RAS),
4/1 Institutskaya str., 630090 Novosibirsk, Russia
E-mail: shchukin@itam.nsc.ru; ancher@itam.nsc.ru; popov@itam.nsc.ru

Using numerical modeling, the possibility of welding aluminum foam plates with an intermediate insert made of monolithic metal is assessed to obtain high-quality permanent connections. The height of the insert is greater than the thickness of the plates. A non-stationary mathematical model of welding under the influence of laser energy on the surface of a non-porous metal insert placed between the ends of the joined plates has been developed. The processes that determine the features of the resulting joints and seams for plates are considered. The material of the plates is foamed technical aluminum A0 with a
thickness of 7 mm with an average porosity of 90 %. The material of the monolithic insert is a similar alloy. To determine the initial and boundary conditions in the calculations, the conditions for experimental studies of welding plates with a CO2 laser with a radiation power of 3 kW at scanning speed of 2 m/min and the resulting samples were used. It has been established that to obtain a weld of satisfactory quality, it is necessary to coordinate the thickness of the plates, their porosity, and the height of the insert and the power of the supplied energy. A feature of the welding process under consideration is the prolonged cooling and solidification of the molten metal, which is a consequence of the high porosity and low thermal conductivity of the plate material. The results of calculations and samples obtained during experimental studies are presented. The calculated characteristics of the joints of foamed aluminum plates are in satisfactory agreement with the results of physical experiments, which confirms the
adequacy of the proposed model and contributes to the understanding of physical processes in the development of technology. The effectiveness of the considered plate welding method is confirmed by the results of tensile testing of the obtained samples.

Keywords: foamed aluminum, laser welding, monolithic intermediate insert, numerical simulation.

DOI: 10.30791/0015-3214-2025-4-33-43

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Investigation of the microstructure of the AlSi10Mg + ZrN composite material obtained by selective laser melting

A. N. Arnautov¹, E. L. Dzidziguri², D. D. Zherebcov², L. V. Fedorenko², S. V. Chernyshikhin<sup>2

1</sup> United company RUSAL, 1 Vasilisy Kozhinoy str., 121096 Moscow, Russia
² NUST MISIS, 4 Leninsky av., building 1, 119049 Moscow, Russia
E-mail: aleksej.arnautov@gmail.com; avroresf@misis.ru; zherebtsovdmitry@misis.ru;
LVFedorenko@edu.misis.ru: s.chernyshikhin@misis.ru

The AlSi10Mg composite material with the addition of various contents of zirconium nitride synthesized by selective laser melting was studied. A synthesis technique was developed, including the preparation of ZrN powder, its mixing with the matrix alloy powder in a planetary ball mill, and printing of volumetric samples. Optimum technological synthesis parameters were determined, providing a high relative density of up to 99.9 % of the resulting composite. It was found that at zirconium nitride concentrations of 10 and 15 wt. %, it partially reacts with the matrix alloy during the synthesis to form small particles with Zr(Al, Si)3 stoichiometry. In the microstructure of the synthesized samples, a uniform distribution of both the initial nitride particles and those formed as a result of the reaction is observed.

Keywords: composite materials, selective laser melting, aluminum alloys, zirconium nitride, microstructure.

DOI: 10.30791/0015-3214-2025-4-44-52

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Spark discharge in a liquid medium as an effective method for synthesis of nanoparticles of multi-element composites with controlled dimensions and morphology

A. A. Zaripov, I. Kh. Khudaykulov, Kh. B. Ashurov

Arifov Institute of Ion-Plasma and Laser Technologies of Uzbekistan Academy of Sciences,
33 Durmon yuli str., 100125 Tashkent, Uzbekistan
Email: i_khudaykulov@mail.ru

This study investigates the method of obtaining nanoparticles of multielement composites in liquid media using spark discharge. Spherical nanoparticles were synthesized, and their sizes were determined using X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM). It was established that the particle sizes are 51.6 nm and 89.2 nm respectively with the difference attributed to the characteristics of the analytical methods used. The influence of discharge power in the range of 40 – 80 W on the morphological characteristics of the nanoparticles was studied. It was shown that increasing the
power leads to a reduction in particle diameter, which is associated with more intensive fragmentation of the initial material and effective cooling of the particles in the liquid medium. It was found that the duration of discharge exposure in the range of 0 – 6000 s does not significantly affect particle size, which is explained by oxidation processes in the electrolyte that prevent agglomeration. X-ray diffraction analysis confirmed the presence of α-Fe, γ-Fe phases, as well as iron oxides and possible compounds of chromium, molybdenum, and copper. In a saline solution (NaCl + H2O), leaching processes promote
the formation of oxide, hydroxide, and chloride phases. The results of the study demonstrate the potential of the spark discharge method for synthesizing nanoparticles of multielement composites with the possibility of controlled variation in their sizes and morphological characteristics, opening up broad prospects for their application in various technological fields.

Keywords: nanoparticles, multi-element composites, liquid media, spark discharge, X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), particle size, discharge power and exposure time, agglomeration.

DOI: 10.30791/0015-3214-2025-4-53-60

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

The effect of long-term annealing on the structure and properties of the Fe – Cr – Al alloy under conditions of high-temperature non-catalytic conversion of hydrocarbon gases and free annealing in air at 1000 °C

S. S. Manokhin^{1, 2}, A. Yu. Tokmacheva-Kolobova¹, I. V. Sedov¹, Yu. R. Kolobov<sup>1, 2

1</sup> Institute of Problems of Chemical Physics of Russian Academy of Sciences,
1 Academician Semenov avenue, 142432 Chernogolovka, Moscow Region, Russia
E-mail: manohin@icp.ac.ru; anastasiia.misis@gmail.com; isedov@icp.ac.ru; kolobov@icp.ac.ru
² Togliatti State University, 14, Belorusskaya str., 445020 Togliatti, Samara Region, Russia

The change in the microstructure of the material of gas-permeable mesh wire matrices made of iron-based alloy (Fehral): Cr (22.5 ± 1 %), Al (5 ± 1 %), impurity elements (2.2 %), the rest — Fe) under conditions of non-catalytic conversion of hydrocarbon gases, and for comparison — after long-term isothermal annealing in air has been studied. The evolution of the structural-phase state of the alloy and the growth of the thickness of the oxide layer formed in the conversion process were studied by optical metallography, scanning and transmission electron microscopy.

Keywords: Fehral, non-catalytic conversion, hydrocarbon gases, microstructure, oxide layer, internal oxidation, electron microscopy.

DOI: 10.30791/0015-3214-2025-4-61-70

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Thermopysical properties and thermodynamic functions of aluminum conductive alloy E-AlMgSi (Aldrey) doped with indium

I. N. Ganiev, F. А. Aliev, R. D. Ismonov, A. M. Safarov, H. O. Odinazoda

Tajik Technical University named after M.S. Osimi,
10 Academician Radjabov Avenue, 734042 Dushanbe, Republic of Tajikistan
E-mail: ganievizatullo48@gmail.com

Aluminum and its alloys are widely used in electrical engineering as a conductor and structural material. As a conductor material, aluminum is characterized by high electrical and thermal conductivity (after copper, the highest level among all technically used metals). Aluminum is also characterized by low density, high corrosion resistance in atmospheric conditions, and high resistance to chemicals. Another advantage of aluminum is that it exhibits neutral behavior towards insulating materials such as oils, varnishes and thermoplastics, also at elevated temperatures. Aluminum is distinguished from other metals by its low magnetic susceptibility, as well as the formation of a non-conducting, easily removable powdery product (Al2O3) in an electric arc. At present, aluminum and its alloys in a number of areas successfully displace traditionally used metals and alloys. One of the promising areas for the use of aluminum is the electrical industry. Conductive aluminum alloys type E-AlMgSi (Aldrey) are representatives of this group of alloys. One of the promising areas for the use of aluminum is the electrical industry. Conducting aluminum alloys of the E-AlMgSi type (Aldrey) are representatives of this group of alloys. The paper presents theresults of a study of the temperature dependence of heat capacity, heat transfer coefficient, and thermodynamic functions of an aluminum alloy E-AlMgSi (Aldrey) with gallium. Research conducted in the “cooling” mode. It is shown that with increasing temperature, the heat capacity, heat transfer coefficient, enthalpy and entropy of the E-AlMgSi (Aldrey) alloy with indium
increase, and the Gibbs energy value decreases. The addition of indium up to 1 wt. % reduces the heat capacity, heat transfer coefficient, enthalpy and entropy of the original alloy and increases the value of the Gibbs energy.

Keywords: aluminum alloy E-AlMgSi (Aldrey), indium, heat capacity, heat transfer coefficient, “cooling” mode, enthalpy, entropy, Gibbs energy.

DOI: 10.30791/0015-3214-2025-4-71-80

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Composition of vapor and thermodynamic characteristics of gaseous molecules of sulfides
of chemical elements of the periodic system

E. K. Kazenas, N. A. Andreeva, G. K. Astakhova, V. A Volchenkova,
O. A. Ovchinnikova, T. N. Penkina, A. A.Fomina, O. N. Fomina

Baikov Institute of Metallurgy and Materials Science of the Russian Academy of Science (IMET RAS),
49 Leninsky prospect, 119334 Moscow, Russia
Е-mail: ekazenas@imet.ac.ru; volch.v.a@mail.ru

The availability of reliable data on the thermodynamics of evaporations of chemical compounds (including sulfides) that are part of the processed raw materials of complex genesis is a necessary component for the development of the physicochemical foundations of pyrometallurgical processes. Our thermodynamic analysis of sulfide evaporation processes showed that many elements of D.I. Mendeleev form chemical compounds with sulfur in both condensed and vapor (gas) states. It was found that the molecular composition of the vapor-gas phase of many sulfides and their mixtures is much more complex and diverse than previously thought. In addition to monomer molecules, various gaseous molecules of these compounds were found in sulfides vapors. Experimental results on the thermodynamics of evaporation and dissociation of sulfides of practically all elements of the periodic system of D.I. Mendeleev are systematized for the first time. A wide range of data on vapour pressure, vapor composition, as well as thermodynamic characteristics of gaseous sulfides obtained from the study of evaporation processes are presented. Temperature dependences of vapour pressure over Me — S systems are established. Tables on enthalpies of atomization and formation of gaseous sulphides vapor composition over sulphides of chemical elements located by groups of the periodic system of D.I. Mendeleev are given.

Keywords: sulfides metals, composition of vapor, enthalpies, atomization, vaporization sulfides, chemical elements, periodic system of D.I. Mendeleev.

DOI: 10.30791/0015-3214-2025-4-81-86